Slope new garage floor?

[RubyRanch]

Hi all, new member here and I have to thank you all for the advice I've gleaned from this forum. I'm laying out the foundation/slab for a new garage, 24x34. The blueprint shows a footer and stem wall(?) all the way around (except at the roll-up doors, of course), but I want to do a monolithic slab with two courses of block to simulate the foundation walls the print shows. My question is that the drawing shows: "4" conc. slab (slope)".

1. Is it standard practice to slope a garage floor? I'm assuming from the back towards the rollup doors?

2. Is it okay to not slope the monolithic slab?

3. If I -did- slope it, that would of course make the building (2-story) unlevel. Do you compensate with the framing of the first-floor walls?

Thanks in advance for any advice you can provide.

Mike D.
S. Carolina

[Bmartin]

Stemwall does not get sloped. Garage slopes toward door usually 1/8"-1/4" per foot for drainage. If it's detached the slope should be optional (depending on local code). If you don't want to slope the floor why do a stemwall at all. You can just pour a slab as if its a house foundation and save a bunch of work. Regardless, whatever the framing sits on needs to be level.

[Sweep]

Apparenty NC has no building code for single family dwellings or you would not need to ask these kind of questions. Find a code (CABO, IRC, etc) and use it. It is not a manual for construction but it will keep you from making mistakes that could cause trouble later.

[RubyRanch]

Bmartin, thanks for the reply. It is in fact a detached garage and what I guess I didn't make too clear is that I -am- planning to just make it a slab, no stem walls. I'll check my local code (South Carolina), and if a detached garage doesn't need to be sloped then I won't slope it. Thanks again.

Mike

[homebild]

South Carolina Code requires a sloped garage floor:

309.3 Floor surface.
Garage floor surfaces shall be of approved noncombustible material. The area of floor used for parking of automobiles or other vehicles shall be sloped to facilitate the movement of liquids to a drain or toward the main vehicle entry doorway.

SC code also requires a minimum footer depth of 12 inches below the surface even for monolithic slab construction.

Best is to place the footer and stem walls, then install a sloped slab to the garage door or a trapped drain that connects to the plumbing system.

[Bmartin]

In my county a garage that is attached to a dwelling must be sloped. A detached building isn't required to be sloped. Although I am in California.